Pappus of Alexandria compiles the Synagoge (Collection) in 8 books c. 320 AD, the most important source of information on ancient Greek mathematics: it preserves and comments on works by Euclid, Apollonius, Archimedes, and others, many of which survived only through Pappus. He states the Pappus-Guldin theorem (centroid of surfaces of revolution), the Pappus hexagon theorem (foundation of modern projective geometry), and the Pappus problem that Descartes chose as the first test of his analytic geometry. Federico Commandino's Latin translation (1588) was the reference geometric text of the late Renaissance. Without Pappus, much of advanced Greek geometry would have disappeared.